In general television broadcasting services, viewers receive broadcasting waves sent from broadcasting stations by receiving terminal devices and view programs which are expressed as audio/video information.
That is, when a program is a real time type program, a receiving terminal device decodes and reproduces in real time a selected stream from those transmitted from a broadcasting station thereby providing video/audio information to a viewer. When a viewer switches the channel, the receiving terminal device decodes and reproduce a newly selected stream instead of the stream being decoded and reproduced previously.
In the case where the real time type program is viewed in the manner as described above, a viewer cannot view a part of a program content during the program being viewed is interrupted and switched to another program to view another program even when the channel is switched back to view again the program originally viewed. Therefore, when the viewer wishes to view a certain program consecutively, the viewer deals with this by video recording the program and viewing it afterwards.
However, it is very troublesome to operate for video recording every time of switching the channel and after all; the viewer has no other way but records the program from the beginning. Further, in case that the program was recorded from the beginning, it is difficult for the viewer to determine the time point to play, so that the viewer has to search the point to resume by conducting high speed play reproduction.
Further, implementation of digital broadcasting services multichannel broadcast and various services will be provided. For example, a service in which a broadcasting station controls receiving terminal devices of the viewers to switch a program by using a transmission stream becomes possible. In this case, when it is controlled to switch the real time program to another program and then to switch back to the former program, viewing of the program is obstructed if a failure of the program content to view is cased, thus it is not satisfactory as a broadcasting service.
Consequently, it is an object of the present invention to provide a broadcasting service which does not cause failure of viewing of program contents even if the program selection is switched.
Particularly it is an object of the present invention to provide a broadcasting service in which, when a real time program which is being viewed by a viewer is interrupted to switch to another program and then switched back to the former program, the program is resumed from the program content at which the program is interrupted.
Further, it is an object of the present invention to provide a broadcasting service in which, when a real time program which is being viewed by a viewer is interrupted to switch to another program and then switched back to the former program, viewing is resumed from the program content at which the program is interrupted and the time difference caused therefrom is solved gradually, so that the viewer does not feel uncomfortable.